Surgical stapling apparatus with powered retraction

ABSTRACT

A surgical stapling apparatus comprises a handle assembly, an actuation shaft having a connector, and a retraction mechanism positioned within the handle assembly. The retraction mechanism includes a motor coupled to a transmission shaft, a first gear rotatably mounted on the transmission shaft, the first gear configured to engage a second gear, a clutch operatively attached to the second gear, a main shaft rotatably connected to the clutch, and a pulley coupled to the main shaft, the pulley being operatively attached to the connector. The connector and the pulley may be attached via a cable. The retraction mechanism may include a spring motor for maintaining the cable in tension. The spring motor may have a spring element wrapped around and interconnecting at least two arbors.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/489,517, filed Jun. 6, 2012, which is a continuation of U.S. patentapplication Ser. No. 13/196,126, filed Aug. 2, 2011, now U.S. Pat. No.8,210,412, which is a continuation of co-pending U.S. patent applicationSer. No. 11/784,804, filed Apr. 9, 2007, now U.S. Pat. No. 8,006,885,the contents of which are incorporated herein by reference in theirentirety.

BACKGROUND

1. Technical Field

The present disclosure relates to a surgical stapling apparatus. Moreparticularly, the present disclosure relates to an endoscopic surgicalstapling apparatus including a mechanism for retracting the actuationshaft of a surgical stapling apparatus.

2. Background of Related Art

Surgical devices capable of fastening tissue portions are well known inthe art. Some of these devices include a knife to cut the tissue thathas been joined by the fasteners. Although the fasteners are typicallyin the form of surgical staples, two-part polymeric fasteners may alsobe employed.

Surgical fastening instruments can include two elongated jaw membersused to capture or clamp tissue. One jaw member typically contains astaple cartridge that houses a plurality of staples arranged in at leasttwo lateral rows while the other jaw member has an anvil that defines asurface for forming the staple legs as the staples are driven from thestaple cartridge. The stapling operation is usually effected by cammembers that translate through the staple cartridge, with the cammembers acting upon staple pushers to sequentially eject the staplesfrom the staple cartridge. A knife may move axially between the staplerows to cut or open the stapled tissue between the rows of staples. U.S.Pat. Nos. 3,079,606 and 3,490,675 disclose examples of this kind ofinstrument.

A stapling apparatus disclosed in U.S. Pat. No. 3,499,591 also applies adouble row of staples on each side of the incision. The patent disclosesa surgical stapler having a disposable loading unit wherein a cam membermoves through an elongate guide path between two sets of staggeredstaple carrying grooves. Staple drive members are located within thegrooves and are positioned in such a manner so as to be contacted by thelongitudinally moving cam member. The staple members eject the staplesin the staple cartridge as the cam member moves axially along theelongate guide path. Other examples of such staplers are disclosed inU.S. Pat. Nos. 4,429,695 and 5,065,929.

Each of the instruments described hereinabove is designed for use inconventional surgical procedures wherein surgeons have direct manualaccess to the operative site. In endoscopic or laparoscopic procedures,however, surgery is performed through a small incision or through anarrow cannula inserted through small entrance wounds in the skin.Endoscopic surgical stapling devices have been developed to address thespecific needs of endoscopic and laparoscopic surgical procedures. A fewexamples of endoscopic surgical stapling devices are disclosed in U.S.Pat. No. 5,307,976; U.S. Pat. No. 5,312,023; U.S. Pat. No. 5,326,013;U.S. Pat. No. 5,332,142; and U.S. Pat. No. 6,241,139, the entirecontents of each of which are incorporated herein by reference.

Tyco Healthcare, LP, the assignee of the present application, hasmanufactured and marketed endoscopic stapling instruments, such as theENDO GIA™ Universal and Universal XL instruments, for a number of years.See FIGS. 1-3. These instruments include a surgical stapling apparatushaving a retraction mechanism to return surgical stapling apparatus to aretracted position. The retraction mechanism may include a pair ofrefractor knobs movably positioned along a barrel portion of a handleassembly. After firing staples, the retraction knobs may be manuallypulled proximally to retract the actuation shaft of the surgicalstapling apparatus to its original position. These instruments haveprovided significant clinical benefits. Nonetheless, improvements tothese instruments are possible.

For instance, it would be extremely beneficial to provide a surgicalstapling apparatus allowing a user to quickly and effortlessly retractthe actuation shaft of the surgical instrument with one hand. It wouldalso be desirable to provide a surgical stapling apparatus with acompact, simple, reliable and ergonomic powered retraction mechanism. Inaddition, it would be beneficial to provide a surgical staplingapparatus with a powered retraction mechanism that can be manuallyoverridden.

SUMMARY

The presently disclosed surgical stapling apparatus has a handleassembly, an actuation shaft having a connector, and a retractionmechanism positioned within the handle assembly. The retractionmechanism includes a motor coupled to a transmission shaft, a first gearrotatably mounted on the transmission shaft, the first gear configuredto engage a second gear, a clutch operatively attached to the secondgear, a main shaft connected to the clutch, and a pulley coupled to themain shaft, the pulley being operatively attached to the connector. Thesurgical stapling apparatus may further include at least one retractionknob operatively attached to a proximal end of the actuation shaft andconfigured for manually returning the actuation shaft to the retractedposition after firing. The actuation shaft may be attached to the atleast one retraction knob via a coupling pin.

A cable may interconnect the proximal end of the connector and thepulley. The cable could be maintained in tension by a spring motorcoupled to the pulley. The spring motor includes a spring elementwrapped around and interconnecting at least two arbors.

The clutch includes first and second discs. The first disc is rotatablyconnected to the second gear and the second disc is slidably androtatably mounted on the main shaft. The clutch may further include abutton configured to turn on the motor and engage the clutch.

An operator may use the retraction mechanism to return the actuationshaft of the surgical stapling apparatus to a retracted position byactivating the motor and engaging the clutch.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1-3 illustrate a prior art surgical stapler;

FIG. 4 is a perspective view of the handle assembly according to anembodiment of the presently disclosed surgical stapling apparatus;

FIG. 5 is a perspective cross-sectional view of the handle assemblyshown in FIG. 2;

FIG. 6 is a perspective view of a portion of an embodiment of thepresently disclosed surgical stapling apparatus;

FIG. 7 is a perspective view of a portion of an embodiment of thepresently disclosed surgical stapling apparatus;

FIG. 8 is perspective view of a connector of an embodiment of thepresently disclosed surgical stapling apparatus;

FIG. 9 is a perspective view of a portion of the retraction mechanism ofan embodiment of the presently disclosed surgical stapling apparatus;

FIG. 10 is a perspective view of a portion of the retraction mechanismof an embodiment of the presently disclosed surgical stapling apparatus;

FIG. 10 a is a perspective view of a portion of the retraction mechanismof an embodiment of the presently disclosed surgical stapling apparatus;

FIG. 10 b is a perspective view of a portion of the retraction mechanismof an embodiment of the presently disclosed surgical stapling apparatus;

FIG. 11 is a perspective view of a portion of the retraction mechanismof an embodiment of the presently disclosed surgical stapling apparatus;and

FIG. 12 is a perspective view of a portion of the retraction mechanismof an embodiment of the presently disclosed surgical stapling apparatus.

DETAILED DESCRIPTION

The embodiments of the present disclosure will now be described indetail with reference to the drawings, in which like reference numeralsdesignate identical or corresponding elements in each of the severalviews.

In the drawings and the description that follows, the term “proximal,”as is traditional, will refer to the end of the stapling apparatus thatis closest to the operator, while the term “distal” will refer to theend of the apparatus that is farthest from the operator.

FIGS. 1-3 illustrate a prior art surgical stapling apparatus generallyreferred as 50. In the interest of brevity, this disclosure will focusprimarily on systems, methods and structures for returning an actuationshaft of surgical stapling apparatus 50 to its retracted position. Adetailed discussion of the remaining components and method of use ofsurgical stapling apparatus 50 is disclosed in U.S. Pat. No. 6,953,139,the entire disclosure of which is incorporated herein by reference.

Surgical stapling apparatus 50 is an endoscopic apparatus and includes ahandle assembly 52 and an elongated body 54 extending therefrom. Asingle use loading unit (“SULU”) 56 is releasably secured to the distalend of elongated body 54. Although the drawings illustrate a SULU 56, aperson having ordinary skill in the art will recognize that other endeffector may be used. SULU 56 includes a tool assembly 57 having acartridge assembly 58 housing a plurality of surgical staples and ananvil assembly 60 movably secured in relation to cartridge assembly 58.As illustrated in FIGS. 1-3, SULU 56 is configured to apply at least onerow of staples. SULUs may have various staple line lengths andconfigurations. Some typical SULUs have staple line lengths measuringfrom about 30 mm to 60 mm in length. SULUs for applying any number ofrows of staples, having staple pockets arranged in various patterns, orend effectors having any other length, are also envisioned. Loadingunits can include those that provide articulating tool assembly or atool assembly that does not articulate, as disclosed in U.S. Pat. No.6,953,139, the disclosure of which is hereby incorporated by referenceherein.

Handle assembly 52 includes a stationary handle member 62, a movablehandle member 64, and a barrel portion 66 defining a longitudinal axis“X.” A rotatable member 68 may be mounted on the distal end of barrelportion 66 to facilitate rotation of elongated body 54 with respect tohandle assembly 52. An articulation lever 70 may also be provided at thebarrel portion 66 adjacent to rotatable knob 68 to facilitatearticulation of tool assembly 57. A pair of retraction knobs 3 aremovably positioned along barrel portion 66 to return surgical staplingapparatus 50 to a retracted position, as will be described in detailbelow.

Referring now to FIGS. 4 and 5, handle assembly 52 includes a retractionmechanism 2 positioned generally along longitudinal axis “X” and abutton 4 for activating retraction mechanism 2. Button 4 is dimensionedand positioned so that a user may easily reach it. Retraction mechanism2 further includes a retraction drive 6 supported within handle assembly52, and a motor 5 operatively coupled to retraction drive 6. An internalor external battery pack, or a cable connecting the retraction mechanism2 to an external power source, may be used to energize motor 5.

Referring to FIGS. 6 and 7, rack assembly 7 has an actuation shaft 8supported within barrel portion 66, and a release plate 9 operativelyassociated with actuation shaft 8. Actuation shaft 8 has a toothed rack28 and its proximal end is connected to the pair of retraction knobs 3via a coupling pin 10. Release plate 9 is configured for movement withrespect to actuation shaft 8 in response to manipulation of retractionknobs 3 or activation of retraction mechanism 2. A pair of spaced apartpins 29 extend outwardly from a lateral face of actuation shaft 8 toengage a pair of corresponding angled cam slots 30 formed in releasedplate 9. Actuation shaft 8 is biased proximally by spring 13. U.S. Pat.No. 7,044,353, the disclosure of which is hereby incorporated byreference herein, describes in detail the structure and manual operationof the rack assembly 7, actuation shaft 8, and release plate 9.

Referring to FIG. 5, handle assembly 52 is provided with a pawl 44 thatis mounted to selectively engage toothed rack 28 and advances theactuation shaft 8 in a distal direction in response to manipulation ofhandle member 64 (see FIG. 2) through an actuating stroke. Pawl 44 ismounted to handle member 64 by a pivot pin 46. The mounting portion ofpawl 44 is curved to interact with an abutment wall 45, and the pawl 44is rotated out of engagement with the toothed rack 28 of actuation shaft8.

To fire apparatus 50 and apply a plurality of surgical fasteners to atissue clamped in tool assembly 57, movable handle member 64 ismanipulated toward a stationary handle member 62. Thereupon, pawl 44engages toothed rack 28 and drives actuation shaft 8 distally. Thedistal advancement of actuation shaft 8 caused by one full stroke ofmovable handle member 64 will be dictated by the size and configurationof the actuation shaft 8. Actuation shaft 8 may have various sizes andconfigurations.

To complete the staple firing operation, movable handle member 64 isonce again approximated toward stationary handle 24, causing pawl 44 toengage toothed rack 28 and advance actuation shaft 8 in a distaldirection another 15 mm. Thus, in one embodiment, two complete strokesof actuation handle 64 may cause actuation shaft 8 to advance 30 mmwithin barrel portion 66, causing the sequential ejection of all thesurgical fasteners in staple cartridge 58. If desired, the operator canincrementally advance actuation shaft 8 by multiple short strokes,wherein the minimum advancement is dictated by the linear distancebetween the teeth on rack 28. Therefore, while two complete strokes of astroke distance of 15 mm can be used (to fire a 30 mm disposable loadingunit), complete strokes are not necessary or required. Surgical staplingapparatus 50 may be configured to have various stroke distances.

With reference to FIGS. 6-8, to enable powered retraction, rack assembly7 may include a distally biased connector 12 having distal and proximalends 12 a, 12 b. A biasing block 13, which is positioned adjacent toproximal end 12 a, biases connecter 12 distally. Connector 12 is mountedon a top portion of rack assembly 7 and has a hole 12 c dimensioned andconfigured for receiving coupling pin 10. The distal end 14 a of a cable14 is attached to the proximal end 12 b of connector 12. The proximalend 14 b of cable 14 is attached to a pulley 21 of retraction drive 6,as seen in FIG. 12.

Referring to FIGS. 9-12, refraction drive 6 includes a transmissionshaft 17 operatively connected to motor 5. A coupling 38 (FIG. 11)interconnects motor 5 and transmission shaft 17. A first gear 18 isrigidly mounted to transmission shaft 17 and configured to engage asecond gear 25. First and second gears 18, 25 effectively reduce thespeed of the rotational motion supplied by motor 5. One skilled in theart will recognize that other speed reducing means may be utilized inlieu of first and second gears 18, 25. Second gear 25 is connected tohollow shaft 26. Hollow shaft 26, in turn, is operatively coupled to afirst disc 23 a of a slip clutch 23. Slip clutch 23 is biased to itsopen position and has a second disc 23 b slidably and rotatably mountedon a main shaft 20. Second disc 23 b may include a tubular portion 33having a flange 34 attached thereto. Tubular portion 33 may surrounds atleast a portion of main shaft 20.

Main shaft 20 is partially surrounded by hollow shaft 26 and isconnected to pulley 21. Additionally, main shaft 20 interconnects pulley21 and spring motor 19. Spring motor 19 may include a spring element 35wrapped around and interconnecting first and second arbors 36, 37.Further, spring motor 19 may be configured to maintain cable 14 intension, thereby preventing its entanglement.

With specific reference to FIG. 10, retraction drive 6 includes a button4 configured to turn on motor 5 and engage clutch 23. Button 4 may havea bottom portion 4 a, an elongated body portion 4 b, a protrusion 4 cconfigured to engage a switch 24, a hole 4 e sized for receiving atubular portion 33 of second disc 23 b, and an upper portion 4 dpivotably coupled to a joint 22 of retraction drive 6. A switch 24 ispositioned adjacent to protrusion 4 c of button 4 and controls theelectrical conduction between a motor 5 and the selected power source.

With reference to FIGS. 10 a and 10 b, an alternative embodiment ofretraction drive 6 includes an activation lever 74 adapted to activateon motor 5. Activation lever 74 has a lower portion 74 a and an upperportion 74 b. Lower portion 74 a is connected to an actuation structure75. A user can manipulate activation lever 74 through actuationstructure 75. Activation lever 74 acts along the major plane of theapparatus 50 to allow ergonomical activation. The upper portion 74 b ofactivation lever 74 is coupled to a cam 76. A lever 77 is operativelyconnected to cam 76 and pivotably coupled to an upper portion ofretraction drive 6. Specifically, lever 77 includes a protrusion 77 aconfigured to manipulate switch 24, an opening 77 b dimensioned toreceive tubular portion 33 (see FIG. 11), and at least one column 77 cconfigured to engage clutch 23. Switch 24 is connected to protrusion 77a of lever 77 and controls the electrical conduction between a motor 5and the selected power source. Cam 76 translates the rotation ofactivation lever 74 with respect to a longitudinal axis “Y” intorotation of lever 77 with respect to longitudinal axis “X.”

In operation, a user fires a staple or any other surgical fastener usingsurgical stapling apparatus 50, as discussed in detail in U.S. Pat. No.7,044,353, the disclosure of which is hereby incorporated by referenceherein, by operating movable handle member 64 to advance actuation shaft8. Thereafter, an operator may automatically return actuation shaft 8 toits retracted position by employing retraction mechanism 2.

To activate retraction mechanism 2, a user must press button 4 to turnon motor 5 and engage clutch 23 when operating the embodiment depictedin FIG. 10. Specifically, as a surgeon activates retraction mechanism 2,button 4 pivots about joint 22 and slides disc 23 b towards disc 23 a,thus engaging clutch 23. In addition, switch 24 allows electricalconnection between a power source and motor 5, thereby energizing motor5.

In the embodiment illustrated in FIGS. 10 a and 10 b, a user can moveactivation structure 75 to manipulate activation lever 77, therebyturning on motor 5 and engaging clutch 23. Specifically, as a user movesactivation structure 75, activation lever 74 rotates with respect tolongitudinal axis “Y.” Cam 76 transforms the rotational motion of lever74 into a rotational motion of lever 77 with respect to longitudinalaxis “X.” Thereafter, lever 77 engages clutch 23 and manipulates switch24 to activate motor 5.

When motor 5 rotates transmission shaft 17, first gear 18 rotates andcauses the corresponding rotation of second gear 25. The interaction offirst and second gears 18, 25 reduces the rotation speed produced bymotor 5. Clutch 23 transfers the rotational motion of second gear 25 tomain shaft 20 and, consequently, to pulley 21. As pulley 21 rotates, itpulls back actuation shaft 8 through cable 14. Upon deactivation ofbutton 4, clutch 23 returns to its open position, and motor 5 is turnedoff. Alternatively, actuation shaft 8 may be manually returned to itsretracted position by pulling retraction knobs 3 proximally. The clutch23, which is biased to its open position, enables the manual retractionof the actuation shaft 8, without engaging the motor 5. The releaseplate 9 removes the pawl from engagement with the actuation shaft 8 sothat the actuation shaft can be retracted either manually or through themotor without interfering with handle 64.

The user of the surgical stapling apparatus 50 can operate the movablehandle member 64 to fire the apparatus 50 and then use the same hand toactuate powered retraction of the actuation shaft 8. After retraction,the used loading unit 56 may be replaced with another loading unit ofthe same or different configuration and staples can again be fired usingthe apparatus 50.

In further embodiments, the firing movement and refraction of anactuation shaft can be actuated through other mechanisms. For example,the retraction mechanism 2 discussed above can be used to retract anactuation shaft that has been driven forwards through a movable handleand gear mechanism, a motor driven mechanism or other powered or manualactuation.

It will be understood that various modifications may be made to theembodiments disclosed herein. Therefore, the above description shouldnot be construed as limiting, but merely exemplifications ofembodiments. For instance, the described surgical stapling apparatus 50may be use in combination with a servomotor, position sensor, slidering, electric brakes and electronic controls to add functions such ascontrolling retraction speed, sensing the limits with automatic stop,etc. Those skilled in the art will envision other modification withinthe scope and spirit of the claims appended thereto.

What is claimed is:
 1. A surgical stapling device comprising: a pair ofjaws movable between open and approximated positions; and a retractionmechanism including: a clutch including first and second discs, at leastone of the first and second discs movable between a disengaged state inwhich the first and second discs are spaced apart and an engaged statein which the first and second discs are engaged with each other forconcomitant rotation; and an actuation shaft configured to effectstapling of tissue disposed between the pair of jaws, the actuationshaft operatively coupled to the second disc, wherein rotation of thesecond disc causes translation of the actuation shaft.
 2. The surgicalstapling device according to claim 1, further comprising a motoroperatively coupled to the first disc, wherein the motor is actuatedwhen the clutch is in the engaged state.
 3. The surgical stapling deviceaccording to claim 1, wherein the retraction mechanism further includesan actuation button movable to transition the clutch between the engagedand disengaged states.
 4. The surgical stapling device according toclaim 2, wherein the retraction mechanism further includes a hollowshaft having the first disc mounted thereon and a main shaft having thesecond disc slidably mounted thereon, wherein a portion of the mainshaft is disposed within the hollow shaft.
 5. The surgical staplingdevice according to claim 4, wherein the retraction mechanism furtherincludes a pulley operatively coupled to the actuation shaft.
 6. Thesurgical stapling device according to claim 4, wherein the retractionmechanism further includes a first gear coupled to the motor and asecond gear mounted on the hollow shaft, the first and second gearsconfigured to reduce the speed of the rotational motion supplied by themotor.
 7. The surgical stapling device according to claim 1, wherein theretraction mechanism further includes a power source to supply electricpower to the motor.
 8. The surgical stapling device according to claim1, wherein the retraction mechanism further includes a cableinterconnecting the actuation shaft and the pulley.
 9. The surgicalstapling device according to claim 1, wherein the retraction mechanismfurther includes a spring motor coupled to the pulley to maintain thecable in tension.
 10. The surgical stapling device according to claim 1,wherein the retraction mechanism further includes a knob coupled to theactuation shaft for manual repositioning of the actuation shaft.
 11. Thesurgical stapling device according to claim 1, wherein the clutch isbiased toward the disengaged position.
 12. The surgical stapling deviceaccording to claim 1, wherein the second disc includes a tubular portiondimensioned to receive at least a portion of the main shaft.